Psychosocial safety climate (PSC) and working conditions, predictors of mental health and antidepressant and opioid use in Australia: a study protocol for longitudinal data linkage

Introduction Work-related stress is a social determinant of global health that represents a huge cost to workers’ health and reduces work performance. In Australia, mental well-being is a pressing national issue—with one in five Australians experiencing mental disorders. Antidepressants are a first-line medication commonly used to treat mental disorders. Recently, Australia has seen a dramatic increase in the use of prescribed antidepressant medications to treat mental health related illnesses. Australia has also seen a dramatic increase in the use of prescribed opioid analgesics for non-cancer pain including opioid use for psychological distress and social stressors. It is plausible a rise in mental health problems and antidepressant and opioid medication use is partly attributable to the corporate climate for worker mental health (ie, the psychosocial safety climate, PSC). This research aims to identify how PSC and workplace conditions contribute to employee well-being and distress that culminate in antidepressant and opioid medication use. Methods/analysis Data will be collected through creative data linkage from the Australian Workplace Barometer (AWB), to medication data (via the Pharmaceutical Benefits Scheme, PBS). The participant sample will include 1372 working Australians from the AWB project from 2009 to 2021. Four waves of longitudinal data from 2009 to 2021 will be used to investigate the plausible link between Australia’s high levels of antidepressant and opioid use and distress at work. The project advances theory by probing the role corporate climate plays in work design, distress, mental health problems and antidepressant and opioid use. It will determine if antidepressant and opioid use has led to an underestimation of work stress effects. Proposed theoretical models will be analysed through linked data, using continuous time structural equation modelling, hierarchical linear modelling, logistic regression and cost estimation. Ethics and dissemination The study has been approved by the Human Research Ethics Committee of the University of South Australia (Ethics Protocol: 203003). Further, approval from the Australian Institute of Health and Welfare Ethics Committee was also granted for linkage of AWB data and PBS data (EthOS Application EO2022/1/1190). Results of the study will be disseminated through worldwide keynotes, key international settings, high-impact peer-reviewed journals, industry conference presentations and media outlets to reach managers, workers, and industry partners. Further, UniSA requires publications from public projects to be held in an institutional repository which fulfils the Australian Research Council’s Open Access Policy.


GENERAL COMMENTS
Thank you very much for the opportunity to learn about this inspiring, very interesting research project, which was possible through this review.Like the Authors, I am convinced that this study protocol may and should be published in the journal BMJOpen.
I have essentially no substantive or ethical comments on this ambitious research project.I believe that the results of this study can lead to very important conclusions.Both its objectives, methods, sample and selection of subjects, and the potential benefits of the results are described very clearly here.The literature cited is current and relevant.The Authors have also addressed the ethical issues of the research.I wish them success in their research.

GENERAL COMMENTS
This is an ambitious study, which using national databases (Australian Workplace Barometer, AWB, Pharmaceutical Benefits Scheme, PBS), wants to answer through a creative method, the relationship between occupational factors, mental health and the use of antidepressants and opioids Introduction: In my opinion, the is a bit disorganized.At the end of the second paragraph, an objective of the study is already introduced.It is preferable that all the objectives are discussed together at the end of the introduction, because otherwise it cuts the discourse a bit.It begins with the increase in use antidepressants, opioids, corporate climate, then depression, again theories of stress at work, corporate climate...In my opinion this part of the introduction has to be rewritten to make it better understood.

Research questions:
In my opinion, the main research question is not fully defined.In fact, the first research question is four.In my opinion, the main research question should be more precisely defined, and perhaps delimited a little more objectives in general, so that it is not confusing or excessive.

Confirmatory analysis Plan:
The statistical method to be carried out is not clearly explained Minor suggestions: Apart from the contribution of each author, it is not necessary the authors be named within the protocol.Check the tenses, and write it in the future if the work has not yet been done.

GENERAL COMMENTS
Overall, this is a well-written manuscript of pre-registered research.The research questions were clear, and the arguments for the study were well articulated.The description of data sources was clear.I do not have major concerns about this pre-registered study.The only thing that was not well described was statistical analysis.Specifically, authors mentioned the use of SEM, HLM, and growth modeling, but it was not clear how these methods would be used to analyze the data.For example, there were four waves of data, but what kinds of changes would be examined?For another example, the authors would look at the relationship between psychosocial demands and antidepressant and opioid use, what types of analysis would be used, correlation or something else?So, this kind of specificity should be clearly described.We know what the authors would examine, but how in terms of specific statistical techniques?
A third example, authors stated "Bayesian analysis will be applied to estimate random intercepts and slopes for individuals to understand future time points for which the individual may be at risk for suicidal ideation."Bayesian analysis is a broad term, and we do not know any specific methods, such as regression or something else in addressing this issue.

VERSION 1 -AUTHOR RESPONSE
Reviewer: 1 Dr. Thomas Gerding, University of Cincinnati Comments to the Author: This sounds like a very interesting study topic.I am curious whether you can find a relationship between occupational stress exposures and antidepressant / opioid medication use.The reviewed protocol outlines your goals and objectives explicitly and to a degree appropriate for publication.
Reviewer: 2 Prof. Agata Chudzicka-Czupała, SWPS University of Social Sciences and Humanities Comments to the Author: Thank you very much for the opportunity to learn about this inspiring, very interesting research project, which was possible through this review.Like the Authors, I am convinced that this study protocol may be published in the journal BMJOpen.I have essentially no substantive or ethical comments on this ambitious research project.I believe that the results of this study can lead to very important conclusions.Both its objectives, methods, sample and selection of subjects, and the potential benefits of the results are described very clearly here.The literature cited is current and relevant.The Authors have also addressed the ethical issues of the research.I wish them success in their research.
Reviewer: 3 Dr.Ricard Navinés , IDIBAPS Comments to the Author: This is an ambitious study, which using national databases (Australian Workplace Barometer, AWB, Pharmaceutical Benefits Scheme, PBS), wants to answer through a creative method, the relationship between occupational factors, mental health and the use of antidepressants and opioids Response (CC): Dear reviewer 3, we appreciate your constructive feedback.

Introduction:
In my opinion, the introduction is a bit disorganized.At the end of the second paragraph, an objective of the study is already introduced.It is preferable that all the objectives are discussed together at the end of the introduction, because otherwise it cuts the discourse a bit.
The aim discussed at the end of the second paragraph has been repositioned to adhere to the traditional structure of an introduction.It begins with the increase in use antidepressants, opioids, corporate climate, then depression, again theories of stress at work, corporate climate...In my opinion this part of the introduction has to be rewritten to make it better understood.
Response (CC): The introduction has been modified for clarity and flow.

Research questions:
In my opinion, the main research question is not fully defined.In fact, the first research question is four.In my opinion, the main research question should be more precisely defined, and perhaps delimited a little more objectives in general, so that it is not confusing or excessive.

Response (CC):
To ensure precision with the main research question we have delimited question as follows; 'Does Psychosocial Safety Climate have primary role, in process pathways linking working conditions to mental health problems and antidepressant/opioid medication use?' Confirmatory analysis Plan: The statistical method to be carried out is not clearly explained Response (CC): The data plan and statistical method section has been modified to include a clearer depiction of the model development and statistical analyses to be conducted.
Minor suggestions: Apart from the contribution of each author, it is not necessary the authors be named within the protocol.Check the tenses, and write it in the future if the work has not yet been done.
Reviewer: 4 Dr. Cody S. Ding, University of Missouri Dear reviewer 4, we appreciate your constructive feedback.
Comments to the Author: Overall, this is a well-written manuscript of pre-registered research.The research questions were clear, and the arguments for the study were well articulated.The description of data sources was clear.I do not have major concerns about this pre-registered study.
The only thing that was not well described was statistical analysis.Specifically, authors mentioned the use of SEM, HLM, and growth modeling, but it was not clear how these methods would be used to analyze the data.For example, there were four waves of data, but what kinds of changes would be examined?For another example, the authors would look at the relationship between psychosocial demands and antidepressant and opioid use, what types of analysis would be used, correlation or something else?So, this kind of specificity should be clearly described.We know what the authors would examine, but how in terms of specific statistical techniques?A third example, authors stated "Bayesian analysis will be applied to estimate random intercepts and slopes for individuals to understand future time points for which the individual may be at risk for suicidal ideation."Bayesian analysis is a broad term, and we do not know any specific methods, such as regression or something else in addressing this issue.
Response (CC): The data plan and statistical method section has been modified to include a clearer depiction of the model development and statistical analyses to be conducted. Reviewer

GENERAL COMMENTS
I am happy with the revision, and the authors explicitly described the purposes of the statistical methods used in the study, which was my only concern before the revision.